Various types of prosthetic heart valves are commonly used in valve replacement surgery to replace a diseased or defective native heart valve, such as an aortic valve, a mitral valve, a pulmonary valve, or a tricuspid valve, of a native human heart. A prosthetic heart valve generally may include a frame or other support structure configured for positioning at an implantation site at or near the native heart valve and anchoring onto the native heart, and an occluder member, such as a multi-leaflet valve, attached to the frame and configured for controlling blood flow through the prosthetic heart valve. Upon implantation of the prosthetic heart valve, the frame may maintain the relative position of the prosthetic heart valve within the native heart, and the occluder member may control blood flow in a manner similar to the native heart valve, thereby restoring desired function of the heart.
According to traditional procedures, heart valve replacement may be performed via open heart surgery, which may require cardiopulmonary bypass and may present a significant risk of certain complications. In recent years, less-invasive procedures for heart valve replacement have been developed, which may eliminate the need for cardiopulmonary bypass and may decrease the risk of complications as compared to open heart surgery. For example, certain prosthetic heart valves may be implanted via a transapical approach, a transatrial approach, a transfemoral approach, a transseptal approach, a subclavian approach, a direct aortic puncture approach, or other vascular access approaches. Each type of approach for implanting prosthetic heart valves may present certain benefits and drawbacks. For example, the transapical approach may provide a direct, “straight shot” approach for replacing certain native heart valves, may allow a physician to leverage past experience in performing transcatheter aortic valve replacement (TAVR) procedures, and may allow a physician to have high degree of control over the prosthetic heart valve and instruments used to implant the heart valve. However, the transapical approach may be challenging in certain patients due to poor tissue quality at the apex of the heart and/or a relatively large outer diameter of the prosthetic heart valve being implanted, may result in left ventricle dysfunction, may present issues of sub-valvular entanglement, and may be more invasive than other potential approaches.
The transatrial approach may provide a direct antegrade approach for replacing certain native heart valves, may avoid sub-valvular anatomy, may eliminate the need to puncture the left ventricle, and may be less sensitive to the size of the outer diameter of the prosthetic heart valve being implanted. However, the transatrial approach may present challenges in steering and navigating the prosthetic heart valve through the anatomy to the desired implantation site, may present a steep learning curve for a physician having experience only with the transapical approach, and may be more invasive than other potential approaches. The transseptal approach may provide a direct antegrade approach for replacing certain native heart valves, may eliminate the need to puncture the left ventricle, and may allow a physician to leverage past experience in performing other procedures through a transseptal puncture. However, the transseptal approach may present challenges in steering and navigating the prosthetic heart valve through the anatomy to the desired implantation site, may require a physician to deliver the prosthetic heart valve over a relatively long distance as compared to other potential approaches, may present challenges in patients having an atrial and/or septal defect, in particular when the prosthetic heart valve has a relatively large outer diameter, and may require venous or arterial access in order to deliver the prosthetic heart valve to the desired implantation site.
Currently, less-invasive approaches are most commonly used in performing aortic valve replacement procedures, although it would be desirable to use less-invasive approaches in replacing mitral valves, pulmonary valves, and/or tricuspid valves in a similar manner. In view of the differences between the aortic valve and the other native heart valves, however, prosthetic heart valves and related instruments configured for aortic valve replacement generally would not be suitable for replacing the other native heart valves. Accordingly, there remains a need for a prosthetic heart valve that is suitable for replacement of the mitral valve, the pulmonary valve, and/or the tricuspid valve. It will be appreciated that a prosthetic heart valve configured for mitral, pulmonary, and/or tricuspid valve replacement may require certain differences in design and function, as compared to prosthetic heart valves configured for aortic valve replacement, in order to be implanted via a less-invasive approach and to function in a suitable manner. In particular, such a prosthetic heart valve should accommodate or conform to the shape and structure of the native heart valve and/or surrounding anatomy without compromising the integrity or function of the surrounding anatomy or the occluder member of the prosthetic heart valve. Such a prosthetic heart valve also should securely anchor onto the native heart tissue to prevent or inhibit migration of the prosthetic heart valve from the implantation site. Further, such a prosthetic heart valve should form a seal against the native heart tissue to prevent or inhibit paravalvular leakage.